Emu XL-7 & MP-7 User's Group

how to get real-time, continuously variable, PWM LFOs. or; another neat 
thing i thought of while trying to figure out something else, realized 
that this is cool in its own way, and just now had a chance to test out. 
enjoy...

LFO1:
 wave: triangle or sawtooth

cords:
 1: LFO1+-  ->  switch  +100
 2: switch  ->  *target*
 3: DC      ->  switch  +0 (controlled by #4)
 4: MIDI-A  ->  CO3     +49-50

this produces a square wave with the duty cycle controlled by knob A (cord 
#4). if cord #4 is set to +50, the pulse can be set flat. if set to 49, it 
can be set to just a tiny pulse (probably 2%?).

of course, if you want something more rounded than a square wave just 
change cord #2 and add one more cord:

cords:
 1: LFO1+-  ->  switch  +100
 2: switch  ->  Lag0    +??
 3: DC      ->  switch  +0 (controlled by #4)
 4: MIDI-A  ->  CO3     +49-50
 5: Lag0    ->  *target*

in this case, the range of cord #2 determines how much of the edges are 
rounded off the square.

note to n00bs (wait a minute... i'm also a n00b): although this example 
uses a knob to adjust the PWM, *any* controller(s) can be used.


-- 
        ...atom

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 http://atom.smasher.org/
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	"Man cannot pretend to he higher in ethics,
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as soon as i hit send, i realized that the PWM LFO trick only covered a 
range from 50-100% (or 0-50%, depending on how its controlled, used and 
how ones brain thinks about such things) duty cycle... how about a way to 
do 0-100% duty cycle?

here it is... enjoy...

LFO1:
  wave: triangle or sawtooth

cords:
  1: LFO1+-  ->  switch  +100
  2: switch  ->  *target*
  3: DC      ->  switch  +0 (controlled by #4)
  4: MIDI-A  ->  CO3     +98-100
  5: DC      ->  switch  -49-50


the ranges shown for cords #4 & #5 control whether the PWM can be driven 
all the way from 0-100% (producing a "flat" output at both ends of the 
range) or reeling in the control just a tiny bit to (about) 2-98% 
(producing a "blip" output at both ends of the range). either way, this 
will output a "standard" 50% duty cycle square-wave at the middle of the 
range.

the previous comments about lag processors and other control sources still 
apply.

i'm also thinking that if a "random" wave is used from the LFO, this could 
be used as a sort of probability generator; spending N% of it's time in 
either a high or low state. that might have some useful applications...


-- 
         ...atom

  ________________________
  http://atom.smasher.org/
  762A 3B98 A3C3 96C9 C6B7 582A B88D 52E4 D9F5 7808
  -------------------------------------------------

 	"A people that values its privileges above its principles
 	 soon loses both."
 		-- Dwight D. Eisenhower